The integration of behavioral and neurophysiological techniques in the study of birdsong has led to significant advances in our understanding of the neural bases for both complex motor systems and vocal learning. This proposal follows a similar logic by integrating the neurophysiology and behavior of song perception in European starlings (Sturnus vulgaris). This research will broaden our understanding of the neural mechanisms that underlie the perception of biologically meaningful acoustic signals. Birdsong is one such biologically meaningful signal, and European starlings, like many species of song birds, use song to recognize individual conspecifics. Starlings are an ideal animal model in which to study the neural basis of song perception because (1) recognition abilities in this species generalize to novel songs from familiar birds, and (2) the behavioral relevance that different acoustic features of song hold for individual vocal recognition is well understood. These two aspects of individual vocal recognition in starlings will allow us to differentiate between neuronal responses that are specific to single songs and those that are specific to individuals, and further, to characterize the nature of these responses with respect to the biological relevance of the specific signal properties that elicit them. This integrative approach to the study of auditory perception in starlings will provide insight into the regions of the auditory forebrain that process complex communication signals, and into the neuronal mechanisms that give rise to recognition behaviors. In so doing, the results of these experiments will contribute significantly to our understanding of the higher-order processing of complex stimuli.